diff --git a/MEV_on_Arbitrum/README.md b/MEV_on_Arbitrum/README.md
index 092b83c..49954a4 100644
--- a/MEV_on_Arbitrum/README.md
+++ b/MEV_on_Arbitrum/README.md
@@ -7,6 +7,7 @@
 <br>
 
 * optimistic rollup
+* currently has a centralized sequencer and whitelisted proof validation while having upgradable contracts
 
 <br>